agreement with the results obtained by the SANDS for oblique IKMT hauls to the 

 surface (Table I). Very high proportions of both the species and specimens are 

 myctophids, although the specimens caught in the MPS tended to be much smaller 

 than those in the IKMT. 



B. Area Bravo 



Area Bravo is located in the southwestern part of the Sargasso Sea. 

 Water depths range from 5300 to 5550 meters with the mixed layer extending down 

 to about 75 meters. The salinity maximum, which marks the core of Subtropical 

 Underwater, is centered close to 100 meters. Eighteen Degree Water, with a 

 mean thickness of about 250 meters, is centered at about 300 meters, and North 

 Atlantic Central Water, underlying this layer, extends to about 900 meters. There 

 were no marked differences in the area in data collected aboard the USNS GILLISS 

 (T-AGOR-4) in November 1965 and the USNS SANDS in March 1966. Surface 

 temperatures in March were cooler by 3-4°C, surface salinities were about 

 0.2%o higher, and Eighteen Degree Water and North Atlantic Central Water 

 both were somewhat shallower compared to November. During November, the 

 main oxygen minimum (3.44 ml/L) occurred at about 810 meters (Figure 9). 

 No oxygen data are available for March, but historical data show the oxygen 

 minimum to lie between 800-950 meters. A complete description of oceanographic 

 conditions in Area Bravo is given by Hunger (1969). 



Collections are available from two trips to Area Bravo. There are 

 10 comparable nighttime tows from the surface scattering layer, three made by 

 the USNS GILLISS and seven by the USNS SANDS, all using the Be MPS. 

 All ten hauls were oblique open net hauls from the surface to as deep as 140 

 meters. 



All three GILLISS tows contained few fish (Table ll-A). In Tow 1C, 

 the only tow that had any appreciable numbers of individual species, Cyclothone 

 braueri accounted for five out of the total of fifteen fish caught, or 33 percent, 

 and the myctophid Lepidop hones goussi, accounted for another 40 percent of the 

 total catch. In the other two tows, the catch was mostly made up of single 

 representatives of different species. Out of the twelve different species of fish 

 taken in all three tows, only three species were found in two or more different 

 tows. These were one gonostomatid, Pollichthys mauli and the myctophids 

 Notolychnus valdiviae and Lepidophanes gaussi . The number of myctophids, 

 however, considered both as percentage of species and percentage of specimens, 

 are lower than in comparable collections from the Gulf of Mexico. Only in 

 collection 3D were more than 50 percent of the fish myctophids and even here 

 only 63 percent of the species and 59 percent of the speciments were myctophids. 



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